Mountune Radiator questions

1. Will upgrading to the Mountune unit help keep my air conditioning cool as well? It seems every time I go to Vegas and it’s 110+ outside my car begins overheating at idle, and even when the temps are under “control” 235* on highway the Air Conditioning never feels cold.

2. I notice a pretty big power hit when it’s hot outside. Will having cooler coolant temps control result in noticeably more stable power?

Last summer in 95° weather, I had my car tap the overheat alert when picking up my wife in a parking lot running the A/C. Our summers easily peak to around 100-105° with high humidity. The rest of the summer, I learned that I was going to have to run my ST without A/C use if I was to take anything other than a 15 minute drive. I found this unacceptable considering my 300WHP Miatas can go a longer before needing to stop the A/C due to heatsoaked ECTs and the whole point of the hot hatch is to have something practical with at least more basic comforts.

I wanted to add my recent 2-3 weeks with my Mountune radiator that I installed last month.

1. Night and day difference in cooling.
   • In 70°+ weather, that car only needs an extra few minutes or miles to fully warm-up.
   • The most I've been able to push ECTs so far is to 196° with A/C running and back to back pulls on boost. With similar driving, I'd have easily pegged 220° in short order and would be turning off the A/C for a while to keep moving.
   • The car sits between 188-190° with regular driving A/C on or off.
2. Aside from filing down the stock radiator fan shroud tabs bit, the radiator was a direct fit.

Ultimately, I definitely feel like the radiator upgrade may cool too much so I'll be watching warm-up temps in the winter, but my objective for non-winter weather is accomplished. To balance out the warm-up a bit, I've swapped my OEM box to a Woosh short-ram (plus the noise is fun and.. a bee filled my ITG panel filter with some honey I found, so needed that out for a bit). I now watch IATs so I can get a better sense of when the car has warmed up. Usually the temps will be a good +40-50° over ambient as I radiator is dumping all the heat into the engine bay and of course is compounded by the heat radiated by the engine and turbo.

I have no plans to upgrade the car further as I enjoy it just fine in it's full-bolt-on state (how I acquired it). With the radiator upgrade, I simply love that I can drive the car hard and not even think about temps overall.

Wow this is a great first hand experience! I appreciate your time for making such an informative post. I do have the same questions for you!

1. Do you notice less powerloss from heat soak?
2. Do you notice the air conditioning being more consistently cold?A/C.